Xfinity internet

   What's wrong with the Xfinity internet?  My internet service goes down every day.  A minute or two this morning the internet was down.  Most days about 3-5 times a day the internet goes down.  The technician replaced the internet modem.  That didn't help.  I think it's the outside cable lines that need to be replacd.  Had that problem before in a diferent county in Florida.